CHAPTER 4. THERMODYNAMICS: THE FIRST LAW

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Review Questions
1. Define open, closed, and isolated thermodynamic systems.
2. What is a state function? List some state functions. List some non-state functions.
3. Define a reversible process.
4. Calculate the work involved in each of the following:
a).
b).
A balloon containing 1 mole of O at 298 K is suddenly ejected into outer space from the
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space shuttle. (Neglect the elastic force of the balloon).
A bubble in a bottle of champagne expands when the bottle is uncorked. Assume the
bubble contains 0.3 mg of CO at 1.5 atm and 5 C, and that the outside pressure is 1 atm).
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c). The expansion in part b is carried out reversibly.
5. Draw a PV diagram for parts (b) and (c) of problem 4.
6. A sufficient amount of heat is transferred to 25.0 g of carbon tetrachloride at its boiling
temperature (76.1 C) to cause it to evaporate inside a container with a frictionless piston. The
external pressure is 1 atm.
a).
b).
c).
d).
Does all the heat get changed into internal energy?
If your answer to (a) was no, explain where the rest goes.
The heat of vaporization of CCl is 30.00 kJ/mol. Calculate the internal energy change for
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this process. (Neglect the volume of the liquid).
After the CCl has evaporated, the outside pressure is reduced to 0.5 atm while the
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temperature is kept constant. Calculate the change in the internal energy and the change in
enthalpy associated with the resulting expansion.
7. Derive the relationship between C P and C V for an ideal gas.
8. Estimate the high temperature value of C for water vapor.
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9. How much heat must be transferred to 3 mole of Ar to raise its temperature from 25 C to 100 C
(a) at constant volume, and (b) at constant pressure?
10. The standard heat of combustion of 1-hexene is -4034 kJ/mol. Calculate its standard heat of
formation.
11. Give a physical explanation of why C P is larger than C V.